Coil components such as inductors, choke coils and transformers (so-called inductance components) have a magnetic material and a coil formed inside or on the surface of the magnetic material. For the magnetic material, Ni—Cu—Zn ferrite or other type of ferrite is generally used.
There has been a need for these coil components of larger current capacity (higher rated current) in recent years, and switching the magnetic material from ferrite as traditionally used, to Fe—Cr—Si alloy, is being studied in order to meet such demand (refer to Patent Literature 1). Fe—Cr—Si alloy and Fe—Al—Si alloy have a higher saturated magnetic flux density than ferrite. On the other hand, their volume resistivity is much lower than that of ferrite.
Japanese Patent Laid-open No. 2007-027354 discloses a method of manufacturing the magnetic material part of a laminated coil component, which is to form magnetic layers using a magnetic paste containing Fe—Cr—Si alloy grains and glass component, laminate the magnetic layers with conductive patterns and sinter the laminate in a nitrogen ambience (reducing ambience), and then impregnate the sintered laminate with thermosetting resin.